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Whenever one of my PCs punches a monster, I start blasting the Pacific Rim soundtrack. It's quite awesome. The PCs enjoy it, I enjoy it, and it's funny. :p And when they get into some bar, I'll sometimes put on the Star Wars cantina. It's all about the right music for the right moment.
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derpApr 8 '14 at 1:06

15 Answers
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Can you imagine watching your favorite movies without a soundtrack? Film directors use music to control audience expectation and trigger emotional responses. As a GM, you too can make use of these techniques at your gaming table.

The simplest plan is to put an album on to play. Slip in a CD, get your iPod out, and press play. I once ran a Sci-Fi campaign with just two soundtrack albums: The Matrix and Ghost in the Shell.

Keep the volume low and the music acts as a backdrop. During battles and other exciting moments pump up the volume and select a more upbeat track. At little more volume can wake up your players, make them fight a little to be heard, and raise their heart rates!

Take it further by using playlists, on your iPod or laptop. Playlists can be much longer than a album and less repetitive. Set up playlists for various situations, and leave them to run through on repeat. As the mood of the game changes, simply switch to another playlist.

To add sound effects such as explosions, spells, or battle sounds you could explore soundboards. Soundboards are simple online flash applications that trigger different sounds at the click of a button. A search online will turn up soundboards with effects that interest you.

For the deepest experience, there are applications available for GMs that combine music and sound effects. The best are RPG Soundmixer and Softrope, they both allow you to build complex soundscapes from small loops of sound. These combine into larger, less repetitive combinations. If you want complete control over sound effects and music at your table then both applications are worth exploring further.

What music can I play?
Find a movie or game that matches the genre of your current RPG and buy the soundtrack. You can often lift soundtracks from a computer game’s install. Baldur’s Gate and all of its sequels, for example, are a great source of background music.

When selecting music, try to avoid anything too distracting. Usually it is best to stick to instrumental tracks, as vocals can be very off-putting. There are exceptions, the last time I used a vocal track was to add atmosphere to a seedy retro jazz bar on a backwater space station.

It is well worth choosing a theme tune for your campaign, it helps focus the player’s attention. Play your theme tune after the players have had their weekly catch up and it unconsciously signals that it is time to start. Signature themes also work well for your reoccurring villains.

One final tip: Keep your finger near the volume control. Volume is a key tool for reacting to your table. Read the table carefully and lower the volume when you can see it is detracting from the experience, then raise it again as the players are reacting positively and having fun!

+1 for quiet ambiance, minimize lyrics. The GM of a dark sci-fi campaign that I played in used Philip Glass CDs, if I remember correctly, to good effect. Not sure about the soundboard/sound effects, be careful with those. They can easily become too intrusive, but could work if mixed well into the background or used for some important (infrequent) special event. Final Fantasy victory music after a battle is popular with my group, to celebrate and lighten the mood a litte. =)
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RMorriseyAug 21 '10 at 5:14

great answer (I would've written something like this myself :D), it touches upon everything I think important. I just have one point to add: besides game and movie OSTs (original soundtracks), "lyricless" instrumental pieces in the categories of ambient, dark ambient, noise and the like can also be great mood enhancers - and there's tons of these freely and legally available online by lesser known bands and composers. for examples, try browsing and exploring bandcamp.com/tag/ambient (or, if you're into cthulhu gaming, go straight for cthulhumusic.bandcamp.com/album/the-fourth :))
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OpaCitiZenNov 12 '10 at 12:04

I will take the dissenting view. I never use music as part of a game, except for very specific narrow situations where it's a plot point or one time gimmick. It is distracting, both for players and for the GM - either you let whatever's on play and it isn't really appropriate to whatever's going on, or you waste GM time fiddling with it and losing momentum - you already have plenty to fiddle with in most games.

Of course we always game in peoples' quiet homes so we don't need to drown anything out, either. Except each other when it gets loud - and sometimes we have enough trouble with people getting loud and talking over each other; adding music adds another couple decibels to everyone's voice.

The only success I had was with appropriate movie sound tracks or classic music played very, very quietly. I don't worry about the music fitting the scene as queueing up a new song takes time and disturbs the flow.

I’ve never enjoyed soundtracks for the sake of soundtracks. But when the PCs ended up in 1969 San Francisco, I did create a soundtrack for them, of action-appropriate music (to the best of my ability) that was also music from the period.

The difference between this and “mood music” is that this was music the player characters were hearing, if not at exactly the “same time” they heard it out-of-game. They were able to talk to the NPCs in character about the lyrics of the songs and gain important clues about the adventure.

I only timed one pair of songs: two tracks from the Charles Manson collection; when those tracks came on, I segued into an encounter with a street guitar player and his adoring fans.

I have used it before, but I don't commonly. IMHO, the three most common mistakes I've seen when people use music are that they turn the volume up too loud, that they choose songs that will distract themselves or other players, and they feel compelled to fiddle with the song selection during the session.

I personally define "too loud" as anything that I can't talk quietly over. I define "songs that distract" as any songs with intelligible lyrics, as well as songs that are genuinely aggravating in some way (Major Lazer's Pon de Floor, for example). Finally, "fiddling" is manipulating any element of the sound system or music player while the game is being played (during break is fine). Making these mistakes results in attention going away from playing to focus on the music.

Computer game sound tracks are great since they are designed to loop in most cases. There are plenty on-line that you can get cheap: Dragon Age, Mass Effect, Assassin's Creed, Silent Hill, Resident Evil (aka Biohazard) and the Witcher just spring to mind as good to set moods.

Finally, Two Steps From Hell are a treasure trove of awesome music. thier producers, Extreme Music are worth a visit as well but you will not be able to buy any tracks, just listen to them.

Well, a lot depends on what you're trying to do. @Buccaneers Guild has pretty much nailed a lot of how to handle setup...the primary thing it to have it all queued up and ready beforehand, so you don't really have to take a break to do anything: if it can just flow completely natually, it can be great.

Volume is important to consider as well: rpging is based on talking, so people should never have to raise their voices; it should be pretty quiet most of the time. They'll still get the effect.

As far as what to play, that's tougher, since styles are so different among DMs/themes/etc. One good source I can recommend are anime soundtracks...you obviously have to preview them beforehand and cull out the inappropriate, but you can get some good stuff on some of them. I've taken some tracks from Wolf's Rain, Last Exile, Spirited Away, etc.

Another popular source is E.S. Posthumus. Very atmospheric and often builds up to a big climax; good for some fight scenes.

Finally, there is Midnight Syndicate. A lot of people like them for their background music for RPGing. A lot of their music tends toward creepy/horror, rather than the classical D&D style, but they also the creators the official D&D soundtrack.

Music, despite being a soundtrack to the story if You fit it well, reduces distractions as GM and players hear less sonds from the surrounding world.

Music is for players ears what a candle is for the eyes. It keeps focus/attention and helps building the atmosphere.

[I'm not a WoD kind of guy - the candles helped me while playing good old fantasy]

Sidenote:
I've once put a tape (yup, it was long ago) in a player and I made the whole session fit the music by improvising situations that the music well ilustrated at the moment. It was quite successful.

Music can be a great addition to any RP session. However, keeping an appropriate choice and volume of the music is essential. One DM I've played with in some D&D sessions likes to keep his iPhone handy with various movie soundtracks. Of course, the music of John Williams (Star Wars, Indiana Jones, etc.) is a common and very effective feature.

I need to keep things simple, so I will usually just use one or two albums. Play heavy metal when they fight. Play Ghost in the Shell soundtrack in a Sci-Fi setting, Ultima V soundtrack in old school fantasy settings, Vagrant Story soundtrack in a dungeon, an album by Lustmord when it gets very creepy, or some folk music when they don't fight.

A success story involved a fair being overrun by evil faery creatures. At first I played generic happy folk music, then I switched to Tom Waits's Black Rider album.

Another success story involved players reaching a door to some overpowered opposition. They did not know and debated the issue. I switched the music to Lustmord and suddenly they were afraid of opening the door. Good for them!

I've tuned a Pandora station. A bit of classical, a bit of matrixy stuff, string quartet covers of metal/rock tunes and some instrumental/electronic. It works pretty well, and I've been tuning it long enough that I almost never have to thumbs down a song anymore. When I get back to some serious GMing I think I'm going to split it into three stations "upbeat for battle", moderate/bland for travel/background and a eerie/spooky channel for adding tension when they're exploring tombs or the like.

I've done it in the past, and it works best, IMO, when using a computer to control the music. Just a soundtrack running music, not so much. And I'd save it for key scenes - the big fight, the romantic interlude, the secret meeting with the king's minister at the hole in the wall inn outside of town...

We never used music to set the tone or anything like that, but we always had some album on in the background. Some of my favourite memories of Roleplaying are evoked when I listen to an old album (Guns and Roses - Appetite for Destructions, Mary Coughlan - Tired and Emotional, Cure - Love Cats - I'm aging myself here) and I remember a particular RPG scenario that we were involved in while listening.

I completely agree with Toby. My "old school" music selections include Led Zeppelin, the Doors, Black Sabbath, the Rolling Stones, etc. Keep it low, and keep it rockin. Don't get fancy with soundtracks or thematic music.
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Tim DrisdelleAug 25 '10 at 20:02

We normally have music on in the background, something that fits the game we're playing and sometimes to fit what we're doing. It's mostly there to set the underlying tempo and feel without being intrusive or dominating.

Sometimes a game becomes strongly linked to the music - I now can't listen to Nick Cave without thinking of Vampire campaigns.

One of our GM's collected a bunch of songs he thought would fit certain situations. He had them on his phone to play at key moments (death of a boss, etc.) I thought it was a failure because, even if I knew the song, I couldn't enjoy or even identify it because of the clipping (high volume setting on a very small speaker) and the three excited conversations going on at the same time.

Sometimes the girls will start a CD or a playlist on YouTube, but that, too, can be overwhelming in the heat of things or when half the party is distracted with a side conversation.